The present invention relates to safe remote control of electrical circuits such as circuits driving electric motors, electric heaters and the like.
It is known to use an electrical starter motor to remotely start and stop a primary motor. Typically, remote actuation is achieved through an electrical circuit having a STOP/START actuator at the remote site and an electrical circuit connecting the STOP/START actuator to a motor energizing circuit at the primary motor site. To enable rapid control of the primary motor, the STOP/START actuator may consist of one or more pushbuttons. When installed in a hazardous area where there is a risk of explosive gases, the remote START/STOP actuator is typically enclosed in a sealed explosion-proof enclosure so as to reduce the chance of an explosion occurring if any spark results from arcing between switch contacts.
While this arrangement may be satisfactory in some environments, further improvements are possible to improve safety and cost.